A new URL has been put in production for Endpoint Manager: https://endpoint.microsoft.com/
While other portal URL’s (https://devicemanagement.microsoft.com/ and Intune blade in Azure portal https://portal.azure.com) will continue to be available, it is recommended to start using this new URL as they will likely start redirecting to the new one and ultimately being removed.
There is no change between the new URL (endpoint) and old one (devicemanagement)